• First recommendation is that you should not use a Slab for a terrain. Reason is that it uses Building materials and it will cause the problem that you are seeing. Also eventually it will slow everything to a crawl because it needs to evaluate every single Building Material Priority, So terrain even if it is flat it should use a Mesh.
• If you still want to use a Slab for this then you will need to place this slab in a dedicated layer with a different intersection number, 0 or 500 and then it will not intersect.
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HTH
Eduardo Rolón AIA NCARB
AC27 US/INT -> AC08Macbook Pro M1 Max 64GB ram, OS X 10.XX latest
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